Compound for forming metal-containing film, composition for forming metal-containing film, and patterning process

Abstract

The present invention is a compound for forming a metal-containing film, containing: at least one metal atom selected from the group consisting of Ti, Zr, and Hf; and a ligand coordinated to the metal atom via an oxygen atom, where the ligand has a cyclic structure (t) selected from a ring having 4 or more carbon atoms and containing 1 or more oxygen atoms, a ring having 3 or more carbon atoms and containing 2 or more oxygen atoms, and a ring having 3 or more carbon atoms and containing 1 or more oxygen atoms and 1 or more heteroatoms other than oxygen atoms. This can provide: a compound for forming a metal-containing film that gives a resist middle layer film that makes it possible to obtain an excellent pattern profile, has high adhesiveness to a resist upper layer film, and suppresses fine-pattern collapse in a fine patterning process of a semiconductor device manufacturing process; a composition for forming a metal-containing film, containing the compound; and a patterning process using the composition.

1 . A compound for forming a metal-containing film, comprising:
 at least one metal atom selected from the group consisting of Ti, Zr, and Hf; and a ligand coordinated to the metal atom via an oxygen atom, wherein   the ligand has a cyclic structure (t) selected from   a ring having 4 or more carbon atoms and containing 1 or more oxygen atoms,   a ring having 3 or more carbon atoms and containing 2 or more oxygen atoms, and   a ring having 3 or more carbon atoms and containing 1 or more oxygen atoms and 1 or more heteroatoms other than oxygen atoms.   
     
     
         2 . The compound for forming a metal-containing film according to  claim 1 , wherein the cyclic structure (t) contains a ring having 4 or more carbon atoms and containing 2 or more oxygen atoms, or a ring having 4 or more carbon atoms and containing 1 or more oxygen atoms and 1 or more heteroatoms other than oxygen atoms. 
     
     
         3 . The compound for forming a metal-containing film according to  claim 1 , wherein the cyclic structure (t) forms a polycyclic structure by being bonded to any one or more of: a cyclic hydrocarbon having 4 to 6 carbon atoms and optionally containing a heteroatom; a cyclic hydrocarbon having 5 or 6 carbon atoms, having one or more carbon-carbon double bonds, and optionally containing a heteroatom; an aromatic ring; and an aromatic heterocycle. 
     
     
         4 . The compound for forming a metal-containing film according to  claim 1 , wherein the cyclic structure (t) is a derivative of an organic acid containing the cyclic structure (t). 
     
     
         5 . The compound for forming a metal-containing film according to  claim 4 , wherein the organic acid is a carboxylic acid. 
     
     
         6 . The compound for forming a metal-containing film according to  claim 1 , wherein the ligand is a derivative of the following structure, 
       
         
           
           
               
               
           
         
         wherein Ra represents a monovalent organic group containing the cyclic structure (t); X represents a group selected from a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, a substituted or unsubstituted, branched alkylene group having 3 to 10 carbon atoms, a substituted or unsubstituted alkylene group having 2 to 10 carbon atoms and containing a carbon-carbon double bond, and a substituted or unsubstituted, branched alkylene group having 3 to 10 carbon atoms and containing a carbon-carbon double bond; and “n” represents 0 or 1. 
       
     
     
         7 . The compound for forming a metal-containing film according to  claim 1 , further comprising a ligand which is a derivative of a silicon compound represented by the following general formula (w), 
       
         
           
           
               
               
           
         
         wherein R A , R B , and R C  each represent any organic group selected from an organic group having 2 to 30 carbon atoms including a crosslinking group of a structure represented by any of the following general formulae (w-1) to (w-3), a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms, 
       
       
         
           
           
               
               
           
         
         wherein R s  represents a hydrogen atom or a monovalent organic group having 1 to 10 carbon atoms; “q” represents 0 or 1; and “*” represents an attachment point. 
       
     
     
         8 . The compound for forming a metal-containing film according to  claim 1 , wherein the compound for forming a metal-containing film is a reaction product of: a metal compound represented by the following formula (a) or a metal-containing compound containing any of a hydrolysate, condensate, and hydrolysis condensate of the metal compound represented by the following formula (a); and a compound having the cyclic structure (t), 
       
         
           
           
               
               
           
         
         wherein M represents any of Ti, Zr, and Hf, L represents a monodentate ligand having 1 to 30 carbon atoms or a polydentate ligand having 1 to 30 carbon atoms, X represents a hydrolysable group selected from a halogen atom, an alkoxy group, a carboxylate group, an acyloxy group, and —NR 1 R 2 , R 1  and R 2  each independently represent a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms, and a+b is 2 to 4, “a” and “b” each representing an integer of 0 to 4. 
       
     
     
         9 . The compound for forming a metal-containing film according to  claim 8 , wherein the formula (a) has a structure of the following formula (a-1), 
       
         
           
           
               
               
           
         
         wherein M represents any of Ti, Zr, and Hf; and R 1A  represents a monovalent organic group having 1 to 20 carbon atoms. 
       
     
     
         10 . A composition for forming a metal-containing film, the composition functioning as a metal-containing film material used in manufacturing a semiconductor, the composition comprising: (A) the compound for forming a metal-containing film according to  claim 1 ; and (B) an organic solvent. 
     
     
         11 . The composition for forming a metal-containing film according to  claim 10 , further comprising one or more of (C) a crosslinking agent, (D) an acid generator, and (E) a surfactant. 
     
     
         12 . The composition for forming a metal-containing film according to  claim 10 , wherein the organic solvent (B) contains, as (B1) a high-boiling-point solvent, one or more kinds of organic solvent having a boiling point of 180° C. or higher. 
     
     
         13 . A patterning process for forming a pattern in a substrate to be processed, comprising the steps of:
 (I-1) applying the composition for forming a metal-containing film according to  claim 10  directly or indirectly onto a substrate to be processed, followed by heating to form a metal-containing film;   (I-2) forming a resist upper layer film directly or indirectly on the metal-containing film by using a photoresist material;   (I-3) subjecting the resist upper layer film to pattern exposure and then development with a developer to form a pattern in the resist upper layer film;   (I-4) transferring the pattern to the metal-containing film by dry etching directly or indirectly while using the resist upper layer film having the formed pattern as a mask; and   (I-5) processing the substrate to be processed directly or indirectly while using the metal-containing film having the formed pattern as a mask to form the pattern in the substrate to be processed.   
     
     
         14 . The patterning process according to  claim 13 , wherein at least one organic resist underlayer film is included between the substrate to be processed and the metal-containing film. 
     
     
         15 . The patterning process according to  claim 13 , wherein the resist upper layer film is formed directly on the metal-containing film. 
     
     
         16 . The patterning process according to  claim 13 , further comprising, after a step of processing a film directly under the metal-containing film while using the metal-containing film as a mask to form the pattern, a step of removing the metal-containing film with a chemical solution. 
     
     
         17 . The patterning process according to  claim 16 , wherein a solution containing a hydrogen peroxide solution and an acid or a solution containing a base, a hydrogen peroxide solution, and water is used as the chemical solution.